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Estimation of thrips (Fulmekiola serrata Kobus) density in sugarcane using leaf-level hyperspectral data
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: ElfatihM Abdel-Rahman --- School of Environmental Sciences, South Africa Mike Way --- , South Africa Fethi Ahmed --- School of Environmental Sciences, South Africa Riyad Ismail --- School of Environmental Sciences, South Africa Elhadi Adam --- School of Environmental Sciences, South AfricaThe aim of this study was to investigate the potential use of leaf-level hyperspectral data to predict the density of sugarcane thrips Fulmekiola serrata (Kobus). A hand-held spectroradiometer was used to make the spectral measurements on spindle leaves of 4-... -
Variation in foliar water content and hyperspectral reflectance of Pinus patula trees infested by Sirex noctilio
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: O Mutanga --- School of Environmental Sciences, South Africa R Ismail --- School of Environmental Sciences, South AfricaThe remote detection and quantification of symptoms associated with declining forest health is critical for the introduction of proper pest monitoring and control measures. Sirex noctilio, the Eurasian wood wasp, is one of the major pests responsible for declining forest... -
The potential of remote sensing technology for the detection and mapping of Thaumastocoris peregrinus in plantation forests
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Z Oumar --- School of Environmental Sciences, South Africa O Mutanga --- School of Environmental Sciences, South AfricaThaumastocoris peregrinus is a sap-sucking insect that feeds on eucalyptus leaves. It poses a major threat to the forest sector by reducing the photosynthetic ability of the tree, resulting in stunted growth and even death of severely infested trees. The... -
Imaging spectroscopy of foliar biochemistry in forestry environments
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: B Majeke JAN van Aardt MA ChoRemote sensing estimates of leaf biochemicals provide valuable information on ecosystem functioning, vitality and state at local to global spatial scales. This paper aims to give an overview of the state of the art of foliar biochemistry assessment in general... -
Predicting soil nitrogen content using narrow-band indices from Eucalyptus grandis canopies as proxy
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Thamsanqa Mzinyane --- University of KwaZulu-Natal, South Africa Jan van Aardt --- Rochester Institute of Technology, UK Fethi Ahmed --- University of Witswatersrand, South Africa Michael Gebreslasie --- School of Agriculture, Earth and Environmental Science, South AfricaOptimal fertiliser applications for sustainable forest stand productivity management, whilst protecting the environment, is vital. This study estimated soil nitrogen content using leaf-level narrow-band vegetation indices derived from a hand-held 350-2 500 nm spectroradiometer. Leaf-level spectral data were collected and subjected... -
Characterisation of a Tunisian coastal lagoon through hyperspectral underwater irradiance
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: DH Nourisson --- Department of Biology, Italy F Scapini --- Department of Biology, Italy L Massi --- Department of Biology, Italy L Lazzara --- Department of Biology, ItalyNorth African coastal lagoons are unique ecosystems that often suffer degradation due to human activities. Therefore, monitoring methods are required to identify stressors and assist with the management of these valuable and often understudied ecosystems. A synthetic indicator of water... -
Determining the optimal phenological stage for predicting common dry bean (Phaseolus vulgaris) yield using field spectroscopy
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Perushan Rajah --- Discipline of Geography, School of Agricultural, Earth and Environmental Sciences, South Africa John Odindi --- Discipline of Geography, School of Agricultural, Earth and Environmental Sciences, South Africa Elfatih Abdel-Rahman --- Discipline of Geography, School of Agricultural, Earth and Environmental Sciences, South Africa Onisimo Mutanga --- Discipline of Geography, School of Agricultural, Earth and Environmental Sciences, South AfricaOn-farm crop productivity and yield prediction are valuable for, among others, designing food policies, on-farm and after-farm planning and pricing, and marketing. Whereas existing prediction approaches are generally reliable, these require extensive and tedious field surveys and adequate ancillary agrometeorological...